added some more stuff to the graph states

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Daniel Knüttel 2020-02-11 10:13:06 +01:00
parent fbdf034710
commit cb0edce102

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@ -505,3 +505,20 @@ $$ \sqrt{-iX} = \frac{1}{\sqrt{2}}\left(\begin{array}{cc} 1 & i \\ i & 1 \end{ar
$$ \sqrt{-iZ} = \exp(-i\frac{\pi}{4})\left(\begin{array}{cc} 1 & 0 \\ 0 & -i \end{array}\right)$$ $$ \sqrt{-iZ} = \exp(-i\frac{\pi}{4})\left(\begin{array}{cc} 1 & 0 \\ 0 & -i \end{array}\right)$$
\subsubsection{Dynamics of Graph States}
So far the graphical representation of stabilizer states is just another way to store
basically a stabilizer tableaux that might require less memory than the tableaux used in
CHP. The true power of this formalism is seen when studying its dynamics. The simplest case
is a local Clifford operator $c_j$ acting on a qbit $j$: The stabilizers of are changed to
$\langle c_j S^{(i)} c_j^\dagger\rangle_i$. Using the definition of the graphical representation
it is clear that just the vertex operators are changed and the new vertex operators are given by
\begin{equation}
\begin{aligned}
o_i' &= o_i &\mbox{if } i \neq j\\
o_i' &= c o_i c^\dagger &\mbox{if } i = j\\
\end{aligned}
\end{equation}
The action of a $CZ$ gate on the state $(V, E, O)$ is less trivial